Conventionally, rope structures such as cords, ropes and cables, are widely used as industrial materials in the fields, for example, land and maritime industries, fisheries industries, and agriculture. Synthetic fibers such as polypropylene, nylon, and vinylon fibers have been used as constituting yarns of such rope structures in the above-mentioned fields. However, the rope structures made of such synthetic fibers are easy to cut due to fatigue during repeated use; therefore it is difficult to elongate their working lifetime.
In particular, in accordance with use subdivision, technical diversification, etc. in the recent land and fishery material fields, there is a tendency that a performance required for products is becoming higher and greater. When these rope structures are used for lifting a high mass object through a sheave, a drum, a pulley, etc. from the ocean, the rope structures are sometimes suffered from severe damage.
For Example, Japanese Laid-open Patent Publication No. 2-210072 (Patent Document 1) discloses a fiber with a higher tenacity and a higher modulus in which an organopolysiloxane represented by the following formula and a fluororesin are adhered to a fiber having a tenacity of not lower than 10 g/d and a modulus of not lower than 400 g/d.

wherein, each of m and n independently represents an integer of not less than 1, X represents a group of OH, NH2, R—OH, or R—NH2, and R represents an alkyl group or a phenyl group.
According to the above-mentioned invention, the abrasion resistance of the fibers is improved by combining the organopolysiloxane with the fluororesin, and further applying them to fibers with a higher tenacity and a higher modulus.
Moreover, U.S. Pat. No. 6,945,153 (Patent Document 2) discloses a braided rope made of a blend of high modulus polyethylene (HMPE) filaments and lyotropic polymer or thermotropic polymer filaments in order to prolong the fatigue life of the braided rope.    [Patent Document 1] Japanese Laid-open Patent Publication No. 2-210072    [Patent Document 2] U.S. Pat. No. 6,945,153